Abstract: The present invention disclosed a method for calculating an oscillation damping ratio of a power grid, and relates to the field of power system operation and control. When a power system oscillates, an oscillation period, two oscillation extreme points, and an oscillation direct current component start to be detected. Then an oscillation decay time constant is calculated according to the two oscillation extreme points and the oscillation direct current component. The oscillation damping ratio is calculated through the oscillation decay time constant and the oscillation period. Compared with a conventional fitting method, the conventional fitting method cannot calculate and analyze the oscillation damping ratio in a cast that a complete oscillation waveform is not obtained. The method proposed by the present inventive patent may complete the calculation of the oscillation damping ratio in a case of obtaining 2 pieces of data, so as to accelerate the speed of calculation.

Abstract: A multi-sensor data fusion-based self-powered online monitoring system for a transmission line includes a plurality of detection nodes, an optical communication receiving and demodulation module, and a data processing module. The detection nodes each include a vibration energy harvesting module, a sensing module, and an optical communication modulation and transmitting module. The detection node uses a triboelectric nanogenerator (TENG) to convert and harvest energy, uses the sensing module to acquire a plurality of types of sensing data, and uses the optical communication modulation and transmitting module to modulate and transmit the sensing data. The optical communication receiving and demodulation module correspondingly receives and demodulates the sensing data, and transmits the sensing data to the data processing module for processing.

Abstract: A semiconductor structure is disclosed. The semiconductor structure includes a staircase structure disposed over a substrate. The staircase structure includes a plurality of layer stacks, where each layer stack is made of a first material layer over a portion of a second material layer. The staircase structure further includes a plurality of landing pads, where each landing pad is disposed over another portion of the second material layer of a respective layer stack.

Abstract: In a solar cell, the back surface of a substrate thereof is provided with alternately distributed emitter zones and back surface field zones. An emitter is formed in each emitter zone, and the emitters are made of boron-doped monocrystalline silicon. A back surface field is formed in each back surface field zone; the back surface fields comprise tunneling oxide layers and polycrystalline silicon layers in stacked distribution, the polycrystalline silicon layers being made of phosphorus-doped polycrystalline silicon, and the tunneling oxide layers being located between a polycrystalline silicon layer and a polycrystalline silicon layer. Positive electrodes are electrically connected to the emitters, and negative electrodes are electrically connected to the back surface fields.

Abstract: Disclosed are a multifunctional cement hydration heat control material and a manufacturing method therefor. The cement hydration heat control material in is a comb polymer having three side chain structures, the three side chain structures are respectively a carboxyl group, a sugar alcohol group, and a polyether structure, and the main chain of the polymer is a carbon chain structure formed by free-radical polymerization of a double bond in a double bond compound monomer. The multifunctional cement hydration heat control material can achieve integration of cement hydration heat control performance, water reduction performance, and shrinkage reduction performance in a same molecule, can achieve control focusing on a performance by means of structural adjustment, does not need multi-component compounding during use, and is more convenient. The control material is non-toxic and water-soluble, can be made to have an appropriate concentration, and is convenient to use.

Abstract: Methods, systems, and computer programs are presented for eliminating bias while training an ML model using training data that includes past experimental data. One method includes accessing experiment results, for A/B testing of a first model, that comprise information regarding engagement with a first set of items presented to users, each item being presented within an ordered list of results. A position bias is calculated for positions within the ordered list of results where the items were presented. A machine-learning program is trained to obtain a second model using a training set comprising values for features that include the calculated position bias. The method includes detecting a second set of items to be ranked for presentation to a first user, and calculates, using the second model, a relevance score for the second set of items, which are ranked based on the respective relevance score and presented on a display.

Abstract: A tunnel oxide layer, an N-type bifacial crystalline silicon solar cell and a method for manufacturing the same are provided. The method for manufacturing the tunnel oxide layer includes forming excess -OH on a back side of a silicon wafer, and depositing the tunnel oxide layer on the back side of the silicon wafer by a Plasma Enhanced Atomic Layer Deposition method. The method for manufacturing the N-type bifacial crystalline silicon solar cell can include following steps: performing cleaning, texturing, boron diffusing, and alkaline polishing on an N-type silicon wafer, sequentially forming a P-type doped layer, a passivation layer, and an anti-reflection layer on a front side of the alkaline-polished N-type silicon wafer, and forming a tunnel oxide layer on a back side of the alkaline-polished N-type silicon wafer, followed by forming an N-type doped polysilicon layer, and after annealing, forming an anti-reflection layer.

Abstract: A method includes providing, within an etch chamber, a base structure including a target layer disposed on a substrate, and an etch mask disposed on the target layer, dry etching, within the etch chamber, the target layer using thionyl chloride to obtain a processed base structure, and after forming the plurality of features. The processed base structure includes a plurality of features and a plurality of openings defined by the etch mask. The method further includes removing the processed base structure from the etch chamber. In some embodiments, the target layer includes carbon. In some embodiments, the dry etching is performed at a sub-zero degree temperature.

Abstract: Disclosed a method for predicting permeability of a multi-mineral phase digital core based on deep learning. In the present disclosure, a three-dimensional digital core is constructed and a pore structure is randomly generated; after a plurality of multi-mineral digital core images is acquired by performing image segmentation on the three-dimensional digital core, permeability corresponding to each of the multi-mineral digital core images is acquired by simulation using multi-physics field simulation software and a multi-mineral digital core data set is constructed based on the plurality of multi-mineral digital core images and the permeability corresponding to each of the multi-mineral digital core images; an SE-ResNet18 convolutional neural network is constructed and trained with the multi-mineral digital core data set; and an image of a multi-mineral core to be predicted is input into the trained SE-ResNet18 convolutional neural network to determine the permeability of the multi-mineral core.

Abstract: Disclosed are various approaches for workflow service application searching. In some aspects, a search query is entered through a search element of a workflow application on a client device. A request is transmitted from a workflow application to a workflow service, to search within an application based on the search query. Application content corresponding to the search query and the application is received from the workflow service. A search result is provided based on the application content and without opening the application on the client device.

Abstract: The present invention discloses an isolation section suppressing shock wave forward transmission structure for a wave rotor combustor and a wave rotor combustor, and belongs to the new concept field of unsteady combustion. The isolation section suppressing shock wave forward transmission structure for a wave rotor combustor includes a wave rotor and a gas inlet port, and the wave rotor is provided with several wave rotor channels. When the wave rotor rotates, the several wave rotor channels communicate with the isolation section sleeve sequentially through the fan-shaped hole. The present invention suppresses reflected shock waves by changing a flow blockage ratio and a shape of the pneumatic valve to consume back transmission pressure, which is beneficial to a fuel intake process, so that steady working of the wave rotor combustor in a state of deviating from a design point can be implemented.

Abstract: The present invention discloses an isolation section suppressing shock wave forward transmission structure for a wave rotor combustor and a wave rotor combustor, and belongs to the new concept field of unsteady combustion. The isolation section suppressing shock wave forward transmission structure for a wave rotor combustor includes a wave rotor and a gas inlet port, and the wave rotor is provided with several wave rotor channels. When the wave rotor rotates, the several wave rotor channels communicate with the isolation section sleeve sequentially through the fan-shaped hole. The present invention suppresses reflected shock waves by changing a flow blockage ratio and a shape of the pneumatic valve to consume back transmission pressure, which is beneficial to a fuel intake process, so that steady working of the wave rotor combustor in a state of deviating from a design point can be implemented.

Abstract: An exercise apparatus and a method thereof relate to the technical fields of physical exercise, training instruments, life cultivation and health preservation, leisure and entertainment, teaching appliances, smart home and the like. Through reverse thinking, by changing a shape, a structure, a function, a control method or/and a using method of an electric scooter, the electric scooter is switched to the fields of physical exercise or/and learning and education. By means of technical characteristics in an attempt to avoid by the technical staff, unexpected technical effects are achieved, and a new purpose of the electric scooter is achieved. The exercise apparatus carries a user to perform automatic round-trip movement, the user correspondingly adjusts physical and mental states to prevent from falling and the exercise apparatus is helpful for improving abilities of balancing, coordination, relaxation, flexibility, concentration and contingency of the user.

Abstract: A synthesis method of ?-nitropyrazole amide compound through asymmetrical catalyzing technique is provided, a nitroalkane and an ?,?-unsaturated pyrazole amide are applied as the raw material, a complex formed by a chiral amine oxide with a rare earth metal compound is served as the catalyst, a 4 ? molecular sieve is served as an additive, the ?-nitropyrazole amide compound can be obtained with a yield more than 99% and enantiomeric excess more than 99% ee. The catalytic system not only has the advantages of simple operation, mild reaction conditions, requiring no acid/base additives, convenient product purification, high yield and enatioselectivity, compliance with green atomic economy, and promising prospects for industrial application, but also allows the obtained ?-nitropyrazole amide compound to undergo some simple chemical conversions to produce some molecules having physiological activities.

Abstract: Provided is a method for preparing a nitrogen-containing aromatic compound through catalytic pyrolysis from organic materials. The method comprises: feeding organic materials and a catalyst into a reactor, to enable the organic material to undergo reactions in the presence of nitrogen and under heating conditions, so as to generate a reaction system flow containing one or more nitrogen-containing aromatic compounds.

Abstract: A paroxetine intermediate, a method for preparing the same, and uses thereof are provided. Specifically, the method includes: reacting a compound of formula I below with a compound of formula II in the presence of an organic base under the catalysis of a complex formed from a chiral amine oxide L and a rare-earth metal compound Ln(OTf)3 to prepare a compound of formula III below: wherein R1 is alkyl, phenyl or benzyl; R2, R3, R4 are each independently C1-C6 alkyl or C6-C10 aryl; the chiral amine oxide L has the following structure: wherein n=1, 2; and R=Ph—, 2,6—Me2C6H3—, 2,6—Et2C6H3—, 2,6-iPr2C6H3—, Ph2CH—.

Abstract: A synthesis method of ?-nitropyrazole amide compound through asymmetrical catalyzing technique is provided, a nitroalkane and an ?,?-unsaturated pyrazole amide are applied as the raw material, a complex formed by a chiral amine oxide with a rare earth metal compound is served as the catalyst, a 4 ? molecular sieve is served as an additive, the ?-nitropyrazole amide compound can be obtained with a yield more than 99% and enantiomeric excess more than 99% ee. The catalytic system not only has the advantages of simple operation, mild reaction conditions, requiring no acid/base additives, convenient product purification, high yield and enatioselectivity, compliance with green atomic economy, and promising prospects for industrial application, but also allows the obtained ?-nitropyrazole amide compound to undergo some simple chemical conversions to produce some molecules having physiological activities.

Abstract: A paroxetine intermediate, a method for preparing the same, and uses thereof are provided. Specifically, the method includes: reacting a compound of formula I below with a compound of formula II in the presence of air organic base under the catalysis of a complex formed from a chiral amine oxide L and a rare-earth metal compound Ln(OTf)3 to prepare a compound of formula III below: wherein R1 is alkyl, phenyl or benzyl; R2, R3, R4 are each independently C1-C6 alkyl or C6-C10 aryl; the chiral amine oxide L has the following structure: wherein n=1, 2; and R=Ph-, 2,6-Me2C6H3-, 2,6-Et2C6H3-, 2,6-iPr2C6H3-, Ph2CH—.

Abstract: Provided is a method for preparing a nitrogen-containing aromatic compound through catalytic pyrolysis from organic materials. The method comprises: feeding organic materials and a catalyst into a reactor, to enable the organic material to undergo reactions in the presence of nitrogen and under heating conditions, so as to generate a reaction system flow containing one or more nitrogen-containing aromatic compounds.

Abstract: A system communicating over a full duplex control channel of a multimedia communication link by using synchronization signals that may also function as a logical link command. Synchronization indicators are exchanged between two communicating devices for maintaining synchronization of a logical link. At least two different types of synchronization signals may be sent between the two devices as synchronization indicators. A first synchronization signal is used by default to maintain synchronization of a logical link. A second synchronization signal is used in place of the first synchronization signal to maintain synchronization of the logical link. The second synchronization signal may be used to imply a virtual link command to indicate that a device is ready to receive data or has successfully received data over the virtual link.